[J Smith]

My brother just bought a rebuilt VW engine for his bug. The guy rebuilt it about 3 years ago, dyno'd it and then it sat in his basement. Apparently it was a very well done rebuild, although I admit I couldn't tell the difference between good and bad.

The engine is in, and it starts. It's runing rough, and if I remove either the #4 or #3 plug wire, it makes no difference. (Firing order is 1-4-3-2). If I remove #1 or #2 plug wire, the engine stumbles and just about dies. It's getting fuel and spark to all cylinders. The exhaust pipes on #3 and #4 don't get very hot though, so it seems it's not firing well. Plug wires are on correctly.
Another thing that may be a clue as to what's wrong: the tach is reading very high, and is kind of erractic.

Is this a timing issue? Any help is much appreciated?